Abrasive projecting machine



June 18, 1940. c. E. UNGER ABRASIVEPROJECTING MACHINE V Filed June 9, 1938 QNM @N Mw mwN Mm. KN NM1 ww n N m.\ M NN Patented June 1s, 1940 42,204,637

UNITED STATES PATENT oFFicE ABRASIVE PROJECTING MACHINEv Chester E. Unger, Mishawaka, Ind., assignor to The American Foundry Equipment Company, Mishawaka, Ind., a corporation of Delaware Application June 9, 1938, Serial No. 212,799

13 Claims. (Cl. 51-9) This invention relates to abrasive projecting tween fixed and movable portions of the machine. iachines and more particularly to a rotary cen- Still another object of the invention is the prorifugal abrasive machine for throwing abrasive vision of a rotary, centrifugal throwing wheel t blasting velocities for cleaning and treating having directional control means, which wheell is ietallic castings, forgings, bars, sheets and like simple and rugged, which is constructed from 5 iaterial, which machine embodies means for pa-rts which can be easily and economically antrolling the direction of flight of the abrasive. formed and assembled, and which can be readily In the operation of abrasive projectors of the replaced and renewed.

Jtary' centrifugal throwing wheel type having Various other features and advantages of the ne or more throwing blades, in order to obtain invention will be apparent from the following Jntrol over the direction of flight of the abraparticular description and from a-n inspection of ve; it is necessary to deliver the abrasive to the the accompanying drawing. dvancing faces of the throwing blades at a pre- Although the novel features which are believed etermined location offset from the axis of rota to be characteristic of this invention will be paron of the blades and during their movement ticularly pointed out in the claims appended 1rough a limited arc. p It is desirable that the hereto, the invention itself, as to its objects and elivery of the abrasive onto the blades be efadvantages, and the manner in which it may be acted accurately, with Va minimum of shock, carried out, may be better understood by referirbulence, Iand spillage or leakage of abrasive. l ring to the following description taken in con- In accordance with an illustrative embodiment nection with the accompanying drawing forming the present invention, the machine comprises a part thereof, in which l rotor having one or more, and preferably a Fig. 1 is a front elevational View of one form urality, of throwing blades mounted for rotaof apparatus constructed in a-ccordance with the on. Abrasive is delivered to a rotatable coninvention, certain of the parts being broken away iner disposed about the axis of the rotor, and and other parts sectioned in order to illustrate 'eferably carried by and forming a portion of the interior construction;

le rotor, which imparts a rotational velocity to Fig. 2 is a transverse cross-sectional View taken le abrasive. The abrasive is scooped or driven along line 2-2 of Fig. 1; and

v its rotational velocity over the abrasive guiding Fig. 3 is a fragmentary, cross-sectional view `ce of a relatively stationary scoop or pick-up of a modified construction. 3o ember and is discharged from the container. In the following description and in the claims,

ne pick-up member delivers the abrasive in a various details will be identified by specific names stributed manner across the inner end portions for convenience, but they are intended to be as the throwing blades and into the path of rotageneric in their application as the art will per- )n thereof and at the desired portion of the mit. Like reference characters denote like parts nth of rotation of the throwing blades. The in the several figures of the drawing. Irasive is urged outwardly along the throwing The blasting machine or abrasive projector to ades and is hurled therefrom at or near the which the present invention relates, comprises a riphery of the rotor at the desired velocity and machine for hurling granulated material at blasta stream, the direction and shape of which can ing velocities for the purpose of surface cleaning 40 controlled by the suitable adjustment of the metal castings, forgings, bars, sheets and like arsition of the discharge 4end of the pick-up ticles. It will be understood that the term ember, other factors remaining the same. abrasive may include steel shot, cracked steel An object of the invention is the provision of a grits, 'quartz sand, and other materials suitable tary, centrifugal, throwing wheel having means for cleaning castings, forgings, bars and sheets.

r delivering abrasive to the throwing blades The abrasive throwing `machine comprises a nder directional control and with a minimum rotor including a dis'c or side wall member I fixed spattering and dispersion. to a rotatably mounted drive shaft 2. as by a hub Still another object of the invention is the prc- 3 secured to the side wall I, as by bolts 4. The sion of arotary, centrifugal throwing wheel hub 3 is secured against rotation on the shaft 2 50 ,ving improved means for delivering abrasive to as by a pin 5, spline, key or other means.

e throwing .blades vwherein the abrasive is de- A plurality of throwing. blades I0 are carried ered` to the throwing blades at a predetermined on the side wall l for rotation therewith. Any :ation and with a minimum of spillage or leaksuitable number .of blades may be employed, but

e and a minimum of grinding of abrasive befrom four to eight blades are usually preferable.

The throwing blades I0 are disposed in spaced and generally radial arrangement and extend from adjacent th periphery of the rotor to`inwardly short of the axis of rotation to provide a central space` I I. A second side wall member I2 may be provided and is suitably secured to the first side wall member I as by studs I4 having reduced ends inserted in the side wall members I and I2 respectively. The blades I0 may be suitably secured in -place by one or more set screws I5 extending through one of the side wall members and entering the recesses I6 in the blades. Preferably, the throwing blades are formed with side flanges 8 and 9 which seat in suitably positioned grooves I8 and I9 in the inner faces of the .side wall members I and I2 respectively. In

order to facilitate reception of abrasive onto the leading face of the blade, the inner end 1 of each blade preferably is formed as a thinned or tapered lip turned toward the direction of rotation, as indicated.

The rotor is provided with a recess 29 concentrically disposed about the axis of rotation of the rotor. 'I'he recess 29 may be defined in any suitable manner and may, if desired, be formed by an integral portion of the side wall member I or hub- 3 or both. The recess preferably is lined by a circular container or recess member 20.

'I'he side wall member I is provided with an opening 2ladapted to receive the recess-member 20 but if desired, may be provided with a countersunk seat to receive the recess member 20. In the illustrative'embodiment, vthe circular recess member 20 extends l,through the opening 2I and seats in a suitably provided recess 28 in the hub 3.

The recess member 20 is formed to define a recess 29 and is provided with a rear wall 22, peripheral wall 23 and a front wall 24 extending inwardly a limited distance from the periphery to define a front opening 25 and provided with a divergent apron or llip 35. 'I'he rear wall 22 may extend'over the entire rear of,l the recess member 20, as illustrated, and thus form a wear plate. It will be noted that the peripheral wall 23 preferably extends over the ends of the grooves I9`and thereby serves to prevent displacement of the throwing blades I0. 'I'he recess member 2 0 is fixed .to the rotor for rotation therewith in a suitable manner, as for example, by one o'r more screws 26 extending through the rear wall 22 andl into the hub.4

Mounted in relatively fixed position adjacent the rotor, as by a bracket 38, is a generally coneshaped shield 21 having its inner end surrounding the lip 35. The shield 21 extends out of the space II and serves to conduct out of the rotor any abrasive which'leaks or spills from the recess member 20. and prevents such abrasive from entering the blades I0.

A feed spout 30l is provided for delivering abrasive 'to the recess 29 and preferably may be formed with a hopper portion 3| to which l abrasive may be delivered in any suitable manner as by aA feed conduit` (no hown). The feed spout also has a nozzle portion 32 extending through the space II `defined by the inner ends .of the throwing blades I0, through the shield 21 and into the recess member 20. The nozzle portion 32 terminat at a point which preferably is determined by the operating characterlistics of. thewheel, which, in the present illustrative embodiment, is a point substantially For the purpose of scooping up abrasive from the recess 29 and delivering it onto the inner ends of the rotating throwing blades in a stream distributed over substantially the entire axial width of the throwing face of the blades buI between the abrasive retaining flanges 8 and S thereof, a pick-up member or channeled scoor 40 is disposed in cooperative relation with the recess 29 and the throwing blades I0. The channeled scoop 40 has its inner or leading end 4I extending into the recess 29 and its outer o1 trailing end terminating closely adjacent the path of rotation of the inner ends of the blade: I0 at a location determined by the direction ir which the abrasive is to be thrown by the wheel The channeled scoop has a channeled or troughbanked that the abrasive is positively guide( from the recess to the throwing blades and'ow: with a minimum of resistance along the'scoop The sidewalls 42 and 43 preferably do not exten: to the inner end of the floor 4I and thusturbulence of abrasive at this point is minimized The inner end 44 of the channeled scoop 40 i: inclined at an angle to the peripheral wall 23 o the recess 29 and is so spaced'therefrom so tha the scoop picks up or skims onl abrasive fron that in the recess and positively guides the abrasive to adjacent the path of the blades. The oute: end 45 is so shaped and positioned that thr abrasive is discharged 'into the path of the blade: at the desired point.` The shield 21 is provide: with a suitable opening 446 through which th' outer end 45 of the scoop extends.

The channeled scoop is `of such width at it.` outer end as to extend substantially over th: entire axial width of the abrasive receiving face: but between the` abrasive confining flanges I and 9 of the blades, as illustrated in Fig. 2, foi the purpose of providing even distribution o: abrasive over the entire axial width of th( abrasive receiving faces of the blades.

The channeled scoop 40 is xedly supporter in any suitable manner and preferably is supported at least in part by the shield 21 and adjustably secured therein, as byl a bracket 35 The feed pipe 30 is supported in a suitabli manner as by a bracket 31, or other suitable sup porting means. Thus, it will be seen that thl shield 21, feed pipe 30, and channeled scoop 4| all are rigidly but adjustably fixed in the Idesire:

v2 by means of lasuitable source of power (noi suitable for abrading.

Abrasive is deliveredto the feed spout 30 ir suitable quantity and at suitable velocity b1 gravity or other feed means (not shown), or .b1 a combination of gravity and other feed means The abrasive falls or is forced lfrom the nozzle portion 32 of the feed spout 30 and is deliverec` into the recess 29 defined by the recess membei 20, which member rotates with vthe rotor ant consequently is traveling at the same. angulai velocity. The abrasive is accelerated and if reacties?f urged outwardly by centrifugal force so that it is retained in the recess 29, and is carried around in a circular path by the rotation of the rotor.

The inner end 44 of the channeled scoop 40 scoops up or skims off a substantially uniform, continuous stream of abrasive from that accumulated in the recess 29 and, owing to its velocity, the abrasive is urged along the channeled scoop and isn guided out of the recess 29 and discharged across the inner ends of the blades I and into the path of the leading faces of the blades I0.

The scoop 40 positively guides the abrasive in a substantially continuous stream to adjacent the path of rotation of the inner ends of the blades and discharges it onto the blades in a stream which may extend substantially over the entire axial width of the throwing faces of the blades and which is relatively uniformly distributed over the width of the throwing faces thereof. The stream of abrasive discharged from the scoop thus does not "cut into the blades and the tendency to wear grooves or channels in Fthe blades is minimized or entirely eliminated.

The floor 4| of the channeled scoop 40 `is so shaped that the centrifugal force on the abrasive prevents the abrasive from falling downwardly away from the scoop and the abrasive thus travels along the scoop until it is discharged into the path of rotation of the blades I0. The outer or trailing end 45 of the channeled scoop 40 is so shaped and positioned that it delivers abrasive into the path of movement of the blades l0 with a velocity outwardly of the rotor and in a sense toward the rotation of the rotor. Thus, the abrasive has an initial velocity in the sense of rotation of the blades and is deposited on the leading faces of the blades with a minimum of shock' and is urged along the leading faces of the blades with a minimum of bounding and turbulence.

The abrasive discharged into the path of the blades is deposited on the leading faces of the blades and is urged outwardly along theblades and finally hurled from the blades at or vnear the periphery of the wheel` in a divergent stream, the direction of which can be controlled by suitable adjustment of the clock-dial position of the discharge end of the scoop relative to the path of travel of the blades, other factors remaining the' same.

Various modifications may be made in theiY structure within the scope of thejnvention. One such modified construction is illustrated in Fig. 3

and comprises a side wall member |0| carrying blades ||0 and supported for rotation by a hubI |03 on a shaft |02. A recess member |20 is provided which is of greater axial width thanf the f recess member 20, illustrated in Figs. 1 to 3. The recess member |20 is provided with'afrear wall |22, peripheral wall |23 and front wall |24, the latter being provided with a lip or apron |35. The recess member |20 is inserted in an opening |2| in the side wall member |0| and seats in a recess |28 in the hub |03.

A shield |21 cooperates with the lip |35 and is adapted to support a channeled scoop |40. A feed spout |30 is provided and suitably supported. The scoop |40 and the feed spout |30 are generally similarto those illustrated in Figs. 1 and 2 but are positioned with their end portions within the recess member |20 offset axially of the rotor sufficiently sothat the abrasive is delivered to the recess |29 at its forward position and is picked upl at itsrear portion.

vof leakage or spillage.

This form of apparatus is operated in a manner generally similar to that above described, except that the abrasive isdelivered to the recess |29 at the forward portion thereof and is carried axially along the recess |29 vas well as circumferentially before being picked up. Thus, the abrasive travels in a generally spiralpath of one or more turns around the axis of the rotor and of suiiicient length to permit the abrasive to be accelerated to the desired angular velocity prior to being picked up by the channeled scoop |40. Preferably, the abrasive is accelerated to an an-- gular velocity approaching or substantially equal to the corresponding portion of the recess member |20, before it is picked up by the channeled scoop.

Where the end of the feed spout is axially displaced from the inner end of the channeled scoop, as in the construction shown in Fig. 3, it is usually preferable to locate the inner end of the channeled scoop axially nearer the blades than is the inner end of the feed spout, thus minimizing:i the distance the abrasive must travel along they channeled scoop.

The present invention .provides abrasive throwing apparatus wherein the abrasive ls delivered to the throwing blades at the desired location positively and effectively and the abrasive is given an initial velocity in the sense of rotation of the throwing blades whereby bounding and turbulence of the abrasive on the blade faces and wear of the blade faces is minimized. The construction is such that the abrasive is delivered to the throwing blades smoothly and in a substantially uniform manner over the entire or a substantial portion of the axial width of the' throwing faces of the blades thereby providing uniform, substantially even -distribution of the abrasive thrown from the blades and providing uniform wear of the leading faces of the blades.

The abrasive is delivered tothe recess in the rotor in a smooth, even manner with a minimum of agitation and turbulence and with a minimum The channeled scoop picks up or skms off abrasive in a substantially continuous manner from that in the recess and delivers it in a substantially continuous stream to the blades. Thus, there is a substantially con-l tinuous flow of abrasive onto the blades, which resultsin a desirably uniform wear of the blades. Any abrasive which is agitated by the leading end of the channeled scoop will be forced centrifugally back into the recess and will not be sucked intov the path of rotation of the blades to cause a stray stream.

'I'he shield may be disposed nrelatively close to the adjacent portion of the rotor and thus carry away any abrasive which leaks or spills from the recess and effectively prevent `such abrasive from falling intothe throwing blades. The channeled scoop terminates closely adjacent the inner ends of the blades and the abrasive is immediately picked up by the leading faces of the throwing blades as it leaves the trailing or outer end of the channeled scoop and thus there is a minimum opportunity of spillage or spattering.

The abrasive is discharged by 'the scoop into the path of rotation of the throwing blades in a stream, the location and direction of which can be closely and accurately controlled and thus the direction of the stream of abrasive hurled from the wheel accordingly can be accuratelyl and closely controlled. The several portions of the apparatus can be readily adjusted in order to adjust and control the direction of discharge of the abrasive from the throwing blades.

The several portions of the machine are of such shapes that they can be formed easily and economically and can be readily assembled and disassembled. 'I'he parts which are subjected to the most wear can be readily replaced and renewed. 'I'he construction is simple and rugged and the wear is minimized by reason of the mode of operation.

While certain novel features of the invention have been disclosed herein, and are pointed out Iin the annexed claims, it will be understood that various omissions, substitutions and changes may be made by those skilled in the art without departing from the spirit of the invention.

What is claimed is:

1. A machine for throwing abrasive at 4blasting velocities comprising a rotor having a plurality of throwing blades extending inwardly short of the axis of rotation of said rotor, a container positioned between the inner ends of said throwing blades and rotatable with said throwing blades, said container defining an abrasive-receiving recess in said rotor, means for supplying abrasive to said recess, and means including a relatively fixed, abrasive-feeding device for removing abrasive from the interior of said recess and conducting the abrasive into the path `of rotation of said blades, saidl feeding device including a scraper portion extending into said abrasive-receiving recess for scraping abrasive therefrom, and a delivery portion outside said recess formed with a generally circumferential wall and a side flange,

said delivery portion lbeing positioned to delivery abrasive to the leading faces of. said blades over a limited portion of their path of rotation.

2. A machine for throwing abrasive at blasting velocities comprising a rotor having a plurality of throwing blades terminating inwardly short of the axis of rotation of the rotor, a container rotatable with said throwing blades and defining an abrasive-receiving recess disposed inwardly from said blades, means for feeding abrasive to said recess, and means including a relatively fixed scoop for guiding abrasive from said recess to said blades, said scoop extending from the interior of said recess outwardly thereof and having a discharge edge at a point closely adjacent the path of rotation of the inner ends of said blades and substantially parallel to the inner ends of said blades.

3. An abrasive throwing machine comprising a rotor having a plurality of blades carried thereon for rotation, means including a rotatable receptacle for imparting rotary movement to abrasive contained therein, means for delivering abrasive to said receptacle, and means including a scoop of channel-shaped cross-section extending from the interior of said receptacle outwardly thereof to a point closely adjacent the path of rotation of the inner portions of said blades for guiding abrasive from said receptacle to said blades and for delivering abrasive to the inner portions of said blades over a limited peripheral distance.

4. Abrasive throwing apparatus comprising a rotor having a plurality of spaced throwing .blades extending in agenerally radial direction from adjacent the periphery to inwardly short of the axis of rotation of the rotor, a container providing an abrasive-receiving recess disposed about the axis of rotation of said rotor"`and oliset axially from said blades, relatively fixed guide means for transferring abrasive from said container to said throwing blades including a portion in said recess and a portion exteriorly of said recess and having a discharge edge disposed at a point adjacent the path of rotation of the inner ends of said blades `and substantially parallel to the inner ends of said blades, and means for feeding abrasive to said container.

5.` An abrasive throwing machine comprising a rotor including a side wall member, a plurality of spaced throwing blades carried by said side wall member and extending in a generally radial direction from adjacent the periphery inwardly short of the axis of rotation of said rotor, and a receptacle seated in and carried by said side wall member and dening a recess disposed inwardly of said throwing blades, a relatively fixed scoop mounted adjacent said rotor and having one end in said receptacle and the other end-ter minating in an edge exteriorly of the receptacle and adjacent the path of travel of said blades and substantially parallel to the inner ends of said blades for guiding abrasive from said receptacle to said blades, and means for feeding abrasive into said receptacle.

6. An abrasive throwing machine comprising a rotor having a plurality of throwing blades mounted for rotation, a receptacle carried by said rotor and having a circumferential wall, an inner retaining wall and an outer retaining wall, said walls defining a recess disposed around the axis of said rotor, means for guiding abrasive from said receptacle to said blades including a scoop member having a trough-shaped abrasive guiding wall extending into said receptacle and having its inner end generally parallel to said ciri cumferential wall, and a portion extending out of `said receptacle and having its outer end generally parallel to and adjacent the inner ends of said blades, and means for delivering abrasive to said annular receptacle. e

7. An abrasive throwingA machine comprising a rotor having a plurality of throwing blades mounted for rotation, a receptacle carried by said rotor and having, a circumferential wall, an inner retaining wall and an outer retaining wall having.

an opening therein, said walls defining an annular recess of generally trough-shaped cross-section disposed around the axis of said rotor, means for guiding abrasive from said receptacle to said blades including a guide element projecting through said opening with an inner portion positioned to scrape abrasive from said recess and an outer portion positioned adjacent the path of movement of. said blades and formed with a surface extending in a generally circumferential direction to guide abrasive into the path of said blades, means for delivering abrasive to said receptacle including a f eed pipe projecting through said opening.

8. An abrasive throwing machine comprising a rotor having a plurality of blades carried thereon for rotation, a receptacle defining a recess in said rotor and including an inturned lip at one side of said recess, means for delivering abrasive to said receptacle, normally stationary shield means cooperating with said lip for limiting the delivery of. abrasive onto said blades except a predetermined portion of the path of rotation of said blades, and a normally stationary guide element extending into said recess and having an abrasive guiding surface for guiding abrasive from said recess to a point closely adjacent the path of rotation of said blades.

9. An abrasive throwing machine comprising a rotor having a plurality of throwing blades.

plurality' of spaced throwing blades, means in said rotor, means for feeding abrasive to said recess, and means for removing abrasive from saidA recess'and discharging it into the path of rotation of said blades, said last means including I a relatively xed, channeled scoop extending into said recess and disposed with its discharge portion terminating closely adjacent the path of rotation of said blades and substantially parallel to the inner ends of said blades.

10. An abrasive throwing wheel comprising'a mounting said blades for rotation, means including an abrasive, receptacle rotatable with said throwing blades for imparting a rotational velocity to'abrasve contained therein. and means including relatively fixed, abrasive-guiding means operative to receive abrasive from' said receptacle to direct abrasive in a generally helical path axially and outwardly of said wheel and discharge said abrasive into the path ofrotation of said throwing blades over a limited circumferential portion of the path of rotation thereof, said abrasive-guiding means including an abrasivereceiving portion in said recess and a discharge portion outside of said recess and terminating adjacent the path of rotation of. the inner ends of said blades.

11. Abrasive throwing apparatus comprising a rotor having a plurality of spaced throwing blades extending in a generallyradial direction from adjacent the periphery to inwardly short of the axis of rotation of the rotor to provide a central opening, means including a receptacle disposed about the axis of rotation and having an opening' at one end, said receptacle having an inturned lip surrounding said-opening, relatively stationary means for guiding abrasive from said recess toward said blades, means for delivering abrasive to said recess, and a relatively stationary shield disposed adjacent and substantially coaxial with said opening and cooperating withl said lip for limiting undesired movement of abrasivev from said receptacle onto said throwing blades.

12. Abrasive throwing apparatus comprising a rotor having a plurality of spaced throwing blades adjacent the periphery to inwardly short of the axis of rotation ofthe rotor to provide a central opening, means including a receptacle defining arecss disposed about the axis of rotation,V said receptacle having an inturned wall, means including a generally conical shield extending from saidinturned wall andthrough said central opening for guiding away'from said blades any` abrasive which leaks from said recess, means for guiding abrasive from said recess to said blades,

4 and means for 'delivering abrasive to said recess.

13. A machine for throwing abrasive at blasting velocities comprising a rotor mounted for high speed rotation and includingia side wall member and a plurality of abrasive propelling extending in a'geea11y-radiardireenon from blades carried by ysaid side wall member and extending from adjacent tl'e periphery inwardly short of the axis of. rotation of the rotor to provide a central abrasive-receiving opening, an abrasive-receiving container in said central opening and rotatable with said rotor for accelerating abrasive, a relatively stationary abrasive guide including a at wall portion disposed in said container in position to scrape abrasive therefrom and guide it in a directionboth axially and outwardly of said rotor, and a at wall portion dis'- posed outside of said container adapted to re-. ceive abrasive from said firstportion and having an abrasive guiding surface extending generally in the direction of travel of the abrasive propelling blades and an edge portion extending generally parallel tol the inner end ,edges of. the abrasive propelling blades in position to deliver abrasive over the inner end edges of said blades at a limited peripheral portion ofthe path of by the advancing faces of said blades and is pro- `pelled therefrom adjacent the periphery of said rotor over a limited arc of the path of rotation, and a feedconduit extending into said container 1 for delivering abrasive thereto.

l cHEsTER E; oriana. 

